1. Field of the Disclosure
The present invention relates to an organic light emitting device, and more particularly, to an organic light emitting device that emits white light.
2. Discussion of the Related Art
An organic light emitting device is provided in such a structure which a light emitting layer is formed between a cathode for injecting electron and an anode for injecting hole. When the electron generated in the cathode and the hole generated in the anode are injected into the light emitting layer, an exciton is produced by the electron and hole bond. Then, when the exciton falls to a ground state from an excited state, the organic light emitting device emits light.
A white organic light emitting device is an organic light emitting device which emits white light. In the case that the white light is emitted in a deposition structure of two light emitting layers which complement each other, when the white light transmits a color filter, it might be difficult to realize high color reproduction range due to a difference between a peak wavelength for each light emitting layer and a transmission rate in the color filter. For example, if a blue emitting layer and a yellow emitting layer are deposited to emit white light, peak wavelengths are formed in a blue wavelength region and a yellow wavelength region. When this white light transmits each of red, green and blue color filters, a transmittance of red or green wavelength region is relatively lower than a transmittance of blue wavelength region, whereby it causes low color reproduction range and low emitting efficiency. The white organic light emitting device is disclosed in Korean Patent Publication No. 10-2011-0057377, which corresponds with US 2011/0121320.